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981.
The experience of 313 reconstructive operations performed in 289 patients with renovascular hypertension is analysed. The importance of choosing the surgical procedure with due regard of the etiology and extent of the pathological process is emphasized. The most effective and frequently employed reconstructive procedures consisted in the author's original technique of transaortic endarterectomy (232 operations), resection of the renal artery with reimplantation of the ostium into the aorta (19 operations), renal artery resection with an end-to-end anastomosis (23 operations). In cases of bilateral lesions of the renal arteries two-stage procedures are recommended, spaced 3-4 months apart. Reconstructive interventions on the single renal artery are described.  相似文献   
982.
Cosmarium turpinii, a fast-growing desmid alga, transforms into protoplasts in 4 h when incubated in a mineral medium + 0.4 M mannitol + 0.5% Cellulysin.  相似文献   
983.
A case in which a spinal subdural haematoma obscured the diagnosis of spinal stenosis is described. The haematoma resulted as a complication of the lumbar puncture necessary for the myelogram. No other aetiological factors were found, but it is suggested that this condition may become more frequent as the result of iatrogenic haemostatic defects.  相似文献   
984.
During EST of schizophrenic (with a prevalent depressive symptomatology) and manic-depressive patients refractory to medicinal therapy, it was possible to find the following conditions. There was a definite advantage in the use of a narcotizing preparation such as epontal with a relaxant listenon compared to a tiopenthal narcosis. This may be due to a short-time narcotic effect of epontal, the absence of postnarcotic symptoms such as expressed apathy, weakness, headaches, which can be observed during 2-3 hours, following tiopenthal narcosis.  相似文献   
985.
A study of the results of surgical treatment of patients with acute cholecystitis showed that cholecystectomy is a safe procedure for the majority of patients during their initial hospitalization and avoids the risk of recurrent attacks and readmissions. Cholecystostomy has a limited place in the treatment of older patients with systemic disease and advanced local disease. Early aggressive management of acute cholecystitis will probably reduce complications of cholecystitis and reduce the need for cholecystostomy.  相似文献   
986.
Specimens of the joint surfaces of the tibia from patients with OA and RA were exposed were examined for bone mineralization, bone formation, osteoid tissue and bone resorption. Judging from the appearance of the osteoblasts in OA the sclerotic changes are mainly focal with relatively little osteogenesis. No osteoclasia was seen in the sclerotic areas. Breakdown of the mineralized cartilage is followed by the development of cysts with highly cellular connective tissue with high osteoblastic activity and osteoclasia. Osteoid tissue is relatively sparse. The changes in RA are more diffuse with a more active osteoblastic activity and widespread zones of osteoid tissue as well as resorption by osteoclasts. It appears as if the increased uptake of 85Sr in OA is more dependent on the occurrence of relatively inert osteosclerosis than on a rapid turnover of the bone tissue.  相似文献   
987.
988.
This paper studies the characterization of corrosion products originated after 1 and 12 weeks' immersion of copper specimens in simulated uterine fluids at pH 6.3 and 8.0 and at 37 °C temperature. The experimental techniques used were X-ray photo-electron spectroscopy, scanning electron microscopy, and energy dispersive X-ray. The compounds found were calcite (CaCO3), calcium phosphate, cuprite (Cu2O) and copper hydroxide (Cu(OH)2). The morphology of corrosion products was a non-uniform, layer showing some paths through which copper ions can be released. In parallel, corrosion products formed on packaged, unused copper-containing intrauterine devices (IUD) were analyzed. Cuprite (Cu2O) and chalcocite (Cu2S) were the main species identified. © 2001 Kluwer Academic Publishers  相似文献   
989.
Following the theory used to study the semiconductor/electrolyte interface the differential capacitance of poly(3-methylthiophene) films has been determined from measurements with a lock-in amplifier and by electrochemical impedance spectroscopy (EIS). According to our findings, the best results were obtained by EIS because the space charge capacitance can be separated from the other capacitances. Using Mott–Schottky plots (C−2 vs. E) we obtained the flat band potential Efb=80 mV and the carrier density N=6×1017 cm−3 for the PMeT film in contact with the electrolyte, where dissolved O2 played the role of the electron acceptor. The determined width of the depletion layer is 0.04 μm. We also investigated the photoelectrochemical response of the PMeT film. The plot of the square of the photocurrent vs. potential yields Efb=90 mV, in good agreement with the EIS measurement. The dependence of the photocurrent with the frequency of the incident light shows that PMeT has a long response time (order of ms), compared to an inorganic semiconductor. The band gap was also determined from the photocurrent spectra. The value obtained, for a direct transition is 1.9 eV and is coincident with the value obtained from the absorption spectra.  相似文献   
990.
Numerical simulations have been carried out for a supersonic two-dimensional flow over open,rectangular cavi-ties(length-to-depth ratios are L/D=1.0 and 3.0)in order to investigate the effect of non-equilibrium condensa-tion of moist air on supersonic internal flows around the cavity for the flow Mach number 1.83 at the cavity en-trance.In the present computational investigation,a condensing flow was produced by an expansion of moist airin a Laval nozzle.The computational results showed that the upstream traveling compression waves becomeweaker than those without the condensation.Consequently,the weaker compression waves cannot excite theshear layer strongly and amplitudes of oscillation in the cavity became smaller than those without the condensa-tion.The occurrence of the non-equilibrium condensation in case of L/D=1.0 affected strongly the amplitude andfrequency of oscillation in the cavity compared with L/D=3.0.  相似文献   
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